A DELAYED HEMOLYTIC TRANSFUSION REACTION DUE TO ANTI-Kp^cANTIBODIES

Abstract

There are few reports on hemolytic transfusion reactions due to anti-Kp^c antibodies against low-incidence red blood cell (RBC) antigens (Kp^c) in Japan and abroad. Here, we report an extremely rare case of hemolysis after a homologous blood transfusion that was subsequently shown to be caused by anti-Kp^c antibodies. A 50-year-old male with chronic kidney disease for 27 years received 4 units of RBCs during hemodialysis. The next day, the patient developed a fever and dyspnea, and had a marked decrease in blood pressure. Hemolysis was suggested based on biochemical data. The Japanese Red Cross Tokyo Blood Center was asked to perform a detailed examination. The resulting report indicated that there were anti-Kp^c antibodies in the patient's blood and confirmed that a unit of blood transfused to him was Kp^c-Ag-positive. Generally, antibodies against low-incidence antigens are considered clinically insignificant because they react below 37°C; however, such antibodies reportedly induce hemolytic disease in fetuses and newborns. In conclusion, while transfusion-related adverse reactions due to antibodies against low-incidence antigens are extremely rare, it is important to note that these antibodies can induce serious hemolysis.